Electronic devices are increasingly used in a greater diversity of applications in which both networking and low power consumption are included. The Power over Ethernet (PoE) system is often provided for certain electronic devices such that electrical power can be passed down Ethernet cabling along with data. Accordingly, a single Ethernet cable, such as category 5 cable or category 6 cable, can provide both a data connection and electrical power to connected devices (such as wireless access points, IP cameras, and IP telephones) without the need to run physically separate power and data cabling. Using the PoE system protocol can save considerable cost when installing a new system or when changes need to be made to an existing system, for example, because the need is reduced for an electrician to install a local AC power point (e.g., when the system is installed) or move the AC power point (e.g., when a device on the network is moved and is no longer close to a power outlet).
To help save power in power-sensitive applications, a Power over Ethernet system can enter a low power mode in which Maintaining Power Signature (MPS) operation is used to signal that a connected device has entered and remains in low power mode. However, the MPS operation itself consumes power while the device is in the low power mode. Accordingly, there is a need to minimize the power consumed by circuitry for MPS operation in low power mode.